#include<iostream>
#include<cmath>
#include<cstdio>
using namespace std;
int main(){
    int a,b,c;
    while(cin>>a>>b>>c){

        if((a+b>c)&&(a+c>b)&&(b+c>a)){
            if(a==b&&a==c)printf("Equilateral triangle!\n");
            else if(a==b||a==c||b==c)printf("Isosceles triangle!\n");
            else printf("Ordinary triangle!\n");
        }
        else printf("Not a triangle!\n");
    }
    return 0;
}
